Directional boring machines and methods for making underground holes are known. A typical directional boring machine is generally configured to drive into the ground a series of drill rods joined end-to-end to form a drill string. At the end of the drill string is a rotating drilling tool. Typically, the rotation of the drill tool is driven by a mud motor or by axially rotating the drill string itself. Various techniques and configurations can be used to provide steering of the drill string during boring operations. Improvements in directional boring machines, drill strings for use with such machines, and methods of directional drilling are needed.